Ring frame and method of manufacturing the ring frame

Abstract

To make it less likely for the paste layer of an adhesive tape to remain when peeling the adhesive tape adhered to a ring frame.SOLUTION: A thin-plate ring frame has an opening in the center, on one surface of which a nickel composite film is arranged in which fine particles of a fluorine compound are dispersed and fixed. A production method of the thin-plate ring frame having the opening in the center includes: performing a degreasing treatment to a stainless-steel frame having the opening in the center; performing a pickling treatment to the stainless-steel frame; performing a nickel strike plating to the stainless-steel frame; performing a nickel polytetrafluoroethylene complex plating to the stainless-steel frame; and forming the ring frame, on the surface of which a nickel polytetrafluoroethylene complex plating layer is formed by cleaning and dehydrating the stainless-steel frame.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a ring frame having an opening in the center with tape applied to close the opening, and a method for manufacturing the same. [Background technology]

[0002] In the device chip manufacturing process, a workpiece such as a semiconductor wafer or package substrate with multiple devices formed on its surface is processed using a processing device. The workpiece is then divided into individual devices to form individual device chips. The formed device chips are then mounted on electronic devices for use.

[0003] When a workpiece is carried into the processing device, the workpiece is integrated with a ring frame having an opening in the center and adhesive tape attached to the ring frame so as to cover the opening, forming a frame unit. In the frame unit, the workpiece is accommodated within the opening of the ring frame.

[0004] Forming the frame unit makes it easier to handle the workpiece. Furthermore, when the workpiece is divided into individual device chips, each device chip remains attached to the adhesive tape, making the resulting device chips easier to handle. Furthermore, when the adhesive tape is expanded radially outward inside the opening of the ring frame after the workpiece is divided, the spacing between the individual device chips increases, making it easier to pick up each device chip.

[0005] After the device chip is separated from the frame unit, the adhesive tape is peeled off from the ring frame so that the ring frame can be reused. However, at this time, the glue layer (adhesive layer) of the adhesive tape tends to remain on the ring frame, making its removal time-consuming.

[0006] Therefore, a technology was developed in which an adhesive tape is attached to a ring frame via a double-sided tape having an adhesive layer whose adhesive strength decreases when a predetermined amount of energy is applied (see Patent Document 1). When peeling the adhesive tape from the ring frame, if the predetermined amount of energy is applied to the double-sided tape in advance to reduce the adhesive strength of the adhesive layer, the adhesive layer is less likely to remain on the ring frame. However, applying sufficient energy to the double-sided tape is time-consuming, and uneven energy can occur, resulting in the adhesive layer remaining on the ring frame.

[0007] Also, a technology has been developed in which a sheet without an adhesive layer is prepared instead of adhesive tape, a frame is prepared with a ring-shaped portion and a pressing portion each having an opening, and the outer periphery of the sheet is clamped between the ring-shaped portion and the pressing portion (see Patent Document 2).However, this required a dedicated structure or an additional process to attach the sheet without an adhesive layer to the workpiece. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-193237 [Patent Document 2] Japanese Patent Application Publication No. 2019-110198 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, there was a need to develop a ring frame that could be used with adhesive tapes with adhesive layers that have been used conventionally, and that would not leave any adhesive layer behind when the adhesive tape was finally peeled off, even if the adhesive tape with adhesive layers was attached.

[0010] The present invention has been made in consideration of such problems, and its purpose is to provide a ring frame in which the adhesive layer of the adhesive tape is less likely to remain when the attached adhesive tape is peeled off, and a method for manufacturing such a ring frame. [Means for solving the problem]

[0011] According to one aspect of the present invention, there is provided a thin plate-shaped ring frame having an opening in the center, One side a region including at least a region in contact with the edge of the opening to 、 A ring frame is provided which is characterized by being provided with a nickel composite coating in which fine particles of a fluorine compound are dispersed and fixed.

[0012] Preferably, the nickel composite coating having the fine particles of the fluorine compound dispersed and fixed therein is also provided on the other surface.

[0013] More preferably, the fluorine compound is any one of polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, and perfluoroalkoxy fluorine resin.

[0014] According to another aspect of the present invention, there is provided a method for manufacturing a thin plate-shaped ring frame having an opening in the center, which comprises degreasing a stainless steel frame having an opening in the center, pickling the stainless steel frame, nickel strike plating the stainless steel frame, nickel polytetrafluoroethylene composite plating the stainless steel frame, and then washing and drying the stainless steel frame to form a surface a region including at least a region in contact with the edge of the opening The present invention provides a method for manufacturing a ring frame, which comprises forming a ring frame having a nickel-polytetrafluoroethylene composite plating layer on the ring frame.

[0015] Preferably, the nickel-polytetrafluoroethylene composite plating is electrolytic plating. [Effects of the Invention]

[0016] The ring frame according to one embodiment of the present invention is provided with a nickel composite coating in which fine particles of a fluorine compound are dispersed and fixed. This nickel composite coating has a low coefficient of friction, which reduces the adhesive force when an adhesive tape is applied to the outer surface. This allows the adhesive tape to be easily peeled off the ring frame, and prevents adhesive residue from remaining on the ring frame.

[0017] Generally, it is desirable for the adhesive tape to be attached to the ring frame with high adhesive strength so that the workpiece can be stably supported. In contrast, the ring frame according to one aspect of the present invention reduces the adhesive strength while ensuring the necessary adhesive strength of the attached adhesive tape, thereby suppressing the residue of the adhesive layer on the ring frame.

[0018] Therefore, the present invention provides a ring frame on which the adhesive layer of the adhesive tape is less likely to remain when the applied adhesive tape is peeled off, and a method for manufacturing the ring frame. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is a perspective view schematically showing a workpiece. [Figure 2] FIG. 10 is a perspective view schematically showing a state in which a ring frame and a workpiece are placed on a chuck table. [Figure 3] FIG. 10 is a perspective view schematically showing how the adhesive tape is placed on the ring frame and the workpiece. [Figure 4] FIG. 4(A) is a perspective view that schematically shows how an unnecessary portion of the adhesive tape is cut off, and FIG. 4(B) is a perspective view that schematically shows a frame unit. [Figure 5] FIG. 2 is a perspective view schematically showing how Ni-PTFE electrolytic composite plating is carried out. [Figure 6] 10 is a flowchart showing the flow of each step in a method for manufacturing a ring frame. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described with reference to the accompanying drawings. The ring frame according to this embodiment is used to form a frame unit when a workpiece is carried into a processing device. Figure 1 is a perspective view schematically showing a surface 1a of a workpiece 1 to be integrated with the ring frame.

[0021] The workpiece 1 is, for example, a substantially disk-shaped substrate made of a material such as Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or other semiconductor material, or a material such as sapphire, glass, or quartz. The glass may be, for example, alkali glass, non-alkali glass, soda-lime glass, lead glass, borosilicate glass, or quartz glass.

[0022] The surface 1a of the workpiece 1 is partitioned by a plurality of planned dividing lines 3 arranged in a grid pattern. Furthermore, devices 5 such as ICs (Integrated Circuits) and LSIs (Large-Scale Integration) are formed in each area of ​​the surface 1a of the workpiece 1 partitioned by the planned dividing lines 3. When the workpiece 1 is divided along the planned dividing lines 3 by a processing device, device chips each equipped with a device 5 can be formed.

[0023] Before the workpiece 1 is loaded into a processing device that divides the workpiece 1, the workpiece 1, the adhesive tape 9, and the ring frame 7 are integrated to form a frame unit 11, as shown in Figure 4(B).

[0024] The workpiece 1 is carried into the processing device in the state of the frame unit 11 and processed. The individual device chips formed in the processing device are supported as they are on the adhesive tape 9. Thereafter, the adhesive tape 9 is expanded radially outward inside the opening 7a of the ring frame 7 to widen the spaces between the device chips, making it easier to pick up the device chips.

[0025] 2 includes a perspective view schematically showing the back side of the ring frame 7 according to this embodiment. The ring frame 7 is a thin plate-like member made of a metal material such as stainless steel (SUS), and has an opening 7a with a diameter larger than that of the workpiece 1. When forming the frame unit 11, the workpiece 1 is positioned within the opening 7a of the ring frame 7 and accommodated in the opening 7a.

[0026] The adhesive tape 9 (see FIG. 3, etc.) is called dicing tape, and is a flexible resin-based tape with flat front and back surfaces. The adhesive tape 9 has a diameter larger than the outer diameter of the ring frame 7, and is composed of a base layer and a glue layer (adhesive layer) provided on one surface of the base layer. The base layer is made of a material such as polyolefin, polyvinyl chloride, or polyethylene terephthalate, and the glue layer is made of an acrylic or rubber-based material, for example.

[0027] When the workpiece 1, adhesive tape 9, and ring frame 7 are integrated, the workpiece 1 and ring frame 7 are placed on the suction surface 2a of the chuck table 2, as shown in Fig. 2. The chuck table 2 is provided with a porous member at the center of its upper part, whose diameter is larger than the outer diameter of the ring frame 7. The upper surface of the porous member becomes the suction surface 2a of the chuck table 2.

[0028] 3, the chuck table 2 has an exhaust passage therein, one end of which is connected to the porous member, and a suction source 2b is disposed at the other end of the exhaust passage. A switching unit 2c is disposed in the exhaust passage, which switches between a communication state and a cutting state. When the switching unit 2c is in the communication state, a negative pressure generated by the suction source 2b acts on an object to be held placed on the suction surface 2a, and the object is held by suction on the chuck table 2.

[0029] 3, adhesive tape 9 is placed on both the workpiece 1 and the ring frame 7 so as to cover them. If adhesive tape 9 having a diameter larger than the suction surface 2a of chuck table 2 is used, when negative pressure from chuck table 2 is applied to the adhesive tape 9, the entire suction surface 2a is covered with adhesive tape 9, and the negative pressure does not leak.

[0030] When adhering the adhesive tape 9 to the workpiece 1 and the ring frame 7, the switching unit 2c is operated to apply negative pressure from the suction source 2b to the adhesive tape 9, etc. Then, the adhesive tape 9 is pressed from above by atmospheric pressure, and the adhesive tape 9 is adhered to the workpiece 1 and the ring frame 7. Note that in order to strengthen the adhesion of the adhesive tape 9 to the workpiece 1 and the ring frame 7, the adhesive tape 9 may be pressed from above with a roller or the like.

[0031] After the adhesive tape 9 has been adhered to the workpiece 1 and the ring frame 7 in this way, the switching unit 2c is again operated to shut off the negative pressure of the suction source 2b. Then, as shown in FIG. 4(A), the adhesive tape 9 is cut on the ring frame 7 using the cutter 4, and the unnecessary portion of the adhesive tape 9 is removed outside the cutting groove 9a. This completes the formation of the frame unit 11 as shown in FIG. 4(B).

[0032] The frame unit 11 is carried into a processing device, which divides the workpiece 1. The formed device chips are then picked up from the adhesive tape 9 and mounted on a predetermined target. The adhesive tape 9 is then peeled off from the ring frame 7 and discarded, and the ring frame 7 is cleaned and reused. At this time, the adhesive layer of the adhesive tape 9 tends to remain partially on the ring frame 7, making removal of the adhesive layer time-consuming.

[0033] Therefore, the ring frame 7 according to this embodiment is provided with a nickel composite coating with fine particles of a fluorine compound dispersed and fixed on its outer surface so that the adhesive layer is less likely to remain when the adhesive tape 9 is peeled off. This composite coating has an extremely small coefficient of friction, allowing the applied adhesive tape 9 to be easily peeled off, and the adhesive layer is less likely to remain on the composite coating. Therefore, the used ring frame 7 can be reused without much effort.

[0034] Next, a method for manufacturing a ring frame 7 having a nickel composite coating on its outer surface with fine particles of a fluorine compound dispersed and fixed thereon will be described. Fig. 6 is a flowchart showing the steps of the manufacturing method. The manufacturing method will be described below using as an example a case in which a ring frame 7 is manufactured by disposing a nickel-polytetrafluoroethylene (Ni-PTFE) composite plating layer as a nickel composite coating on a stainless steel frame.

[0035] A stainless steel frame 13 (see FIG. 5) is used as a raw material for manufacturing the ring frame 7. For example, the stainless steel frame 13 is a conventional ring frame that is integrated with a workpiece 1 such as a semiconductor wafer and an adhesive tape 9 such as a dicing tape to form a frame unit 11. An opening with a diameter larger than the diameter of the workpiece 1 is formed in the center of the stainless steel frame 13.

[0036] First, the stainless steel frame 13 is subjected to a degreasing treatment S10. The degreasing treatment S10 is a treatment in which various types of dust, oil, and other organic matter adhering to the surface of the stainless steel frame 13 are removed from the stainless steel frame 13 using an organic solvent or alkaline solution. By performing the degreasing treatment S10, it becomes possible to form a uniform film when forming a Ni-PTFE composite plating layer on the outer surface of the stainless steel frame 13, as will be described later.

[0037] In the degreasing process S10, a liquid such as an organic solvent or alkaline solution is heated and the stainless steel frame 13 is immersed in the liquid. For example, an organic solvent such as trichloroethylene, tetrachloroethylene, or trichloroethane is used in the degreasing process S10. Alternatively, an alkaline solution such as an aqueous solution of sodium hydroxide or sodium carbonate is used in the degreasing process S10.

[0038] Next, the stainless steel frame 13 is subjected to an acid pickling treatment (acid activation treatment) S20. The acid pickling treatment S20 is a treatment in which oxide films, rust, and residual oils on the surface of the stainless steel frame 13 are removed from the stainless steel frame 13 using a strong acid such as sulfuric acid or hydrochloric acid, thereby exposing the base material of the stainless steel frame 13. Furthermore, when the acid pickling treatment S20 is performed, a minute uneven shape is formed on the surface of the stainless steel frame 13, which increases the adhesion of the Ni-PTFE composite plating layer, which will be formed later, to the outer surface of the stainless steel frame 13.

[0039] Next, nickel strike plating S30 is performed on the stainless steel frame 13. Nickel strike plating S30 is a process for applying a base plating to the surface of the stainless steel frame 13. Nickel strike plating S30 is performed to prevent the formation of a new passive film on the surface of the stainless steel frame 13 after the pickling treatment S20, while also increasing the adhesion of a Ni-PTFE composite coating (described below) to the surface.

[0040] In nickel strike plating S30, the stainless steel frame 13 and nickel metal plate are immersed in a strongly acidic plating bath called a Wood's bath, which is composed of nickel chloride and hydrochloric acid, and electricity is passed between the stainless steel frame 13 and the nickel metal plate. This forms a nickel strike plating layer as a thin base film on the surface of the stainless steel frame 13.

[0041] Next, nickel polytetrafluoroethylene (Ni-PTFE) composite plating S40 is performed on the stainless steel frame 13 having the nickel strike plating layer formed on its surface. FIG. 5 is a perspective view showing a schematic view of the Ni-PTFE composite plating S40 being performed. The Ni-PTFE composite plating S40 is performed, for example, in a plating apparatus 6 having a rectangular container 8 made of vinyl chloride. In FIG. 5, the components inside the container 8 are drawn with solid lines for ease of explanation, but the container 8 and the plating solution 10 contained therein are not necessarily transparent.

[0042] The container 8 contains a plating solution 10. The plating solution 10 contains nickel sulfamate, nickel chloride, boron, a primary brightener, a secondary brightener, and a polytetrafluoroethylene dispersion (PTFE dispersion). The PTFE dispersion is a liquid in which, for example, PTFE particles with a particle size of 1 μm or less are dispersed at 25 to 28 vol %. A nickel metal plate 16 is used as the anode.

[0043] In Ni-PTFE composite plating S40, a stainless steel frame 13 and a nickel metal plate 16 are immersed in a plating solution 10 contained in a container 8. Then, an electric current is passed through the plating solution via a wiring 12 connected to the stainless steel frame 13 and a wiring 14 connected to the nickel metal plate 16.

[0044] At this time, the current density on the surface of the stainless steel frame 13 was set to 5 A / dm 2 The electrolytic plating is performed for a time until the thickness of the Ni-PTFE composite plating layer reaches 2 μm or more and 10 μm or less. Specifically, the time is expected to be 2 minutes or more and 10 minutes or less. When the Ni-PTFE composite plating S40 is performed, a nickel composite coating with dispersed and fixed PTFE particles, i.e., a Ni-PTFE composite plating layer, is formed on the surface of the stainless steel frame 13.

[0045] Thereafter, the stainless steel frame 13 is removed from the container 8, and is washed and dried (S50). Specifically, the stainless steel frame 13 with the plating solution 10 attached thereto is immersed in water contained in a cleaning tank to remove the attached plating solution 10, and the stainless steel frame 13 is removed from the cleaning tank and dried to remove the attached water. This results in the formation of a ring frame 7 having a nickel-polytetrafluoroethylene composite plating layer formed on its surface as a nickel composite coating.

[0046] In the process of the ring frame manufacturing method described above, that is, between each step, the stainless steel frame 13 may be washed with a liquid such as water as needed. Washing the stainless steel frame 13 with water or the like can prevent excessive progress of chemical reactions. In addition, the stainless steel frame 13 becomes easier to handle.

[0047] Here, the surface of the ring frame 7, which is coated with a nickel composite coating having fine particles of polytetrafluoroethylene (PTFE) dispersed and fixed thereon as a fluorine compound, has an extremely small coefficient of friction. Therefore, when an adhesive tape 9 is applied to the surface of the ring frame 7, the adhesive force thereof is small. Therefore, after processing the workpiece 1 included in the frame unit 11, the adhesive tape 9 can be easily peeled off from the ring frame 7, and the adhesive layer of the adhesive tape 9 is unlikely to remain on the ring frame 7.

[0048] Generally, it is desirable that the adhesive tape 9 be attached to the ring frame with high adhesive strength so as to stably support the workpiece 1. However, in the ring frame 7 according to this embodiment, the adhesive strength is reduced while ensuring the necessary adhesive strength of the attached adhesive tape 9, thereby preventing the adhesive layer from remaining on the ring frame 7.

[0049] Furthermore, if a nickel composite coating with fine particles of a fluorine compound dispersed and fixed therein is formed on the outer surface of the ring frame 7, the ring frame 7 will also be resistant to dirt other than the adhesive layer. For example, when processing the workpiece 1, processing chips are generated from the workpiece 1 and the processing tool. The processing chips may come into contact with the outer surface of the ring frame 7, and may adhere to the ring frame 7.

[0050] However, when a nickel composite coating with dispersed and fixed fine particles of a fluorine compound is formed on the outer surface, processing debris is less likely to adhere to the ring frame 7. Even if processing debris does adhere to the ring frame 7, the processing debris can be easily removed from the ring frame 7 in a subsequent cleaning process. In other words, the ring frame 7 is resistant to dirt other than the adhesive layer.

[0051] In the above embodiment, a nickel composite coating having dispersed and fixed fine particles of a fluorine compound is formed on all outer surfaces of the ring frame 7, but this aspect of the present invention is not limited to this. For example, in the ring frame 7 according to one aspect of the present invention, a nickel composite coating having dispersed and fixed fine particles of a fluorine compound may be formed on only one surface of the ring frame 7, and the nickel composite coating may not be formed on the other surface.

[0052] In this case, the worker can select the surface of the ring frame 7 to which the adhesive tape 9 is to be attached when integrating the workpiece 1, the ring frame 7, and the adhesive tape 9 to form the frame unit 11. For example, if the worker does not want to leave the adhesive layer of the adhesive tape 9 on the ring frame 7 so that the ring frame 7 can be easily reused, the adhesive tape 9 can be attached to the one surface of the ring frame 7 on which the nickel composite coating is formed when forming the frame unit 11.

[0053] On the other hand, depending on the weight of the workpiece 1 and the processing to be performed on the workpiece 1, it may be desirable to adhere the adhesive tape 9 to the ring frame 7 with strong adhesive force. In this case, it is advisable to adhere the adhesive tape 9 to the other surface of the ring frame 7 on which the nickel composite coating is not formed. In this way, when the nickel composite coating is provided on only one surface of the ring frame 7, the surface to which the adhesive tape 9 is applied can be selected depending on the purpose.

[0054] Here, in order to form the nickel composite coating only on a part of the outer surface of the ring frame 7, it is advisable to carry out a process such as Ni-PTFE composite plating S40 while masking the other parts of the outer surface of the ring frame 7. To perform the masking, methods such as applying chemical-resistant tape or providing a chemical-resistant resist can be considered.

[0055] The nickel composite coating may be provided not only on one surface but also on the other surface of the ring frame 7. In this case, the worker does not have to worry about which surface of the ring frame 7 to stick the adhesive tape 9 to.

[0056] In the above embodiment, the fluorine compound particles dispersed and fixed in the nickel composite coating are polytetrafluoroethylene (PTFE), but the material of the fluorine compound is not limited to this. The type of fluorine compound may be appropriately selected depending on the properties required for the outer surface of the ring frame 7.

[0057] That is, the fluorine compound dispersed and fixed in the nickel composite coating may be, for example, any one of polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), and perfluoroalkoxy fluororesin (PFA).

[0058] Furthermore, in the above embodiment, the Ni-PTFE composite plating S40 is formed by electrolytic plating, but this is not a limitation of the present invention. That is, the Ni-PTFE composite plating S40 may be formed by electroless plating.

[0059] In addition, the structures, methods, etc. according to the above-described embodiments can be modified as appropriate without departing from the scope of the object of the present invention. [Explanation of symbols]

[0060] 1 Workpiece 3 Planned division line 5 Devices 7 Ring Frame 9 adhesive tape 9a cutting groove 11 Frame Unit 13 Stainless steel frame 2 Chuck table 2a Suction surface 2b Suction source 2c Switching section 4 cutters 6. Plating equipment 8 containers 10 Plating solution 12,14 Wiring 16 Nickel metal plate

Claims

1. A thin plate-shaped ring frame having an opening in the center, A ring frame characterized in that one surface thereof is provided with a nickel composite coating having fine particles of a fluorine compound dispersed and fixed therein, in an area including at least an area in contact with the edge of the opening.

2. 2. The ring frame according to claim 1, wherein the nickel composite coating having the fine particles of the fluorine compound dispersed and fixed therein is also provided on the other surface of the ring frame.

3. 3. The ring frame according to claim 1, wherein the fluorine compound is any one of polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, and perfluoroalkoxy fluorine resin.

4. A method for manufacturing a thin plate-shaped ring frame having an opening in the center, comprising: A stainless steel frame with a central opening is degreased, The stainless steel frame is subjected to an acid pickling treatment; The stainless steel frame is nickel strike plated; The stainless steel frame is subjected to nickel polytetrafluoroethylene composite plating, The stainless steel frame is washed and dried to A method for manufacturing a ring frame, comprising forming a ring frame having a nickel-polytetrafluoroethylene composite plating layer formed on a surface thereof, at least in an area including an area in contact with the edge of the opening.

5. 5. The method for manufacturing a ring frame according to claim 4, wherein the nickel-polytetrafluoroethylene composite plating is electrolytic plating.

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